Patients with atrial fibrillation, particularly patients with non-valvular atrial fibrillation, are five times more likely of having a stroke than patients without atrial fibrillation. This increased risk is believed to original from the left atrial appendage (LAA), a muscular pouch within the pericardium and connected to the left atrium of the heart. Blood may pool within the LAA, and this pooled blood may have a tendency to form clots, which can dislodge from the LAA and form emboli. In fact, it is believed that over 90% of clots form in the LAA.
Consequently, removing or excluding (occluding) the LAA is believed to reduce the risk of stroke, especially in patients with atrial fibrillation. LAA occlusion (which may also be referred to herein as exclusion or ligation) may be accomplished by using an endocardially placed occlusion device, for example, a Transcatheter Patch (Custom Medical devices, Athens, Greece), the PLAATO™ device (ev3, Sunnyvale, Calif.), or WATCHMAN® device (Boston Scientific, Marlborough, Mass.). Alternatively, LAA occlusion may at least partially involve an epicardially placed occlusion device. There are two commonly used methods of performing LAA occlusion: one method uses endocardial and epicardial magnetized guides that stabilize the LAA by the magnetic force between the two guides through the LAA tissue. Once the LAA is stabilized, a snare is passed over the LAA and used to ligate or suture the LAA (for example, the LARIAT™ (SentreHeart, Inc. Redwood City, Calif.)). The other method involves a purely epicardial approach in which, via subxiphoid access, the LAA is identified and inserted into a clamp device (for example, the ATRICLIP® (AtriCure, Inc. West Chester, Ohio)). The clamp then remains implanted within the patient. All of these methods are meant to isolate the LAA and prevent blood clots from exiting the LAA and traveling as emboli through the bloodstream.
Of course, each of these methods has its drawbacks. For example, the magnetized guide technique may accommodate a variety of anatomies, but it requires endocardial access. The clamp technique, on the other hand, may be less versatile, but does not require the more invasive endocardial access.
It is therefore desirable to provide a method, system, and device for performing LAA occlusion that involves a purely epicardial approach and is adaptable to a variety of anatomies.